Novel creaseproofing compositions, and methods and creaseproofed textiles



United States Patent 3,148,021 NOVEL CREASEPRQOFHQG COMPOSITIONS, AND METHGDS AND CREASEPROOFED TEXTILES Thomas C. Allen and Harold J. Watson, Danville, Va., assignors to Dan River Mills, Incorporated, Danviile, Va., a corporation of Virginia No Drawing. Filed Aug. 28, 1961, Ser. No. 134,074 7 Claims. (Cl. 8-129) This invention relates to compositions and methods for creaseproofing textiles and creaseproofed textiles obtained therefrom. More particularly, the invention is directed to the treatment of textiles to provide thereto improved crease-resistance without chlorine-retention problems or strength loss incident to such problems.

Heretofore, a large variety of chemicals, including thermosetting aminoplast resins, fiber reactive compounds, e.g., epihalohydrins, dihalohydroxy organic compounds, unsaturated sulfones, and the like have been employed with varying degrees of success in creaseproofing textiles. In general, the amine or aminoplast textile treating chemicals are plagued with the serious drawback that when applied to and cured on textiles, they retain chlorine during bleaching operations and release retained chlorine during subsequent heating operations, thereby damaging the textile. Chlorine-retention has been a subject of extensive corrective research with no complete success. The fiber reactive compounds generally are not concerned with chlorine retention problems but require the use of relatively expensive reactants and, in general, require close critical controls in applying them to textiles in order to provide satisfactory crease-resistance without weakening the textile fibers or adversely affecting the hand of the treated textiles. Another general disadvantage of textiles treated with previous creaseproofing chemicals is the rela tive impermanence of the crease-resistance of said textiles to multiple home and/ or commercial laundering resulting in complete or substantial loss of crease-resistance.

It is a principal object of this invention to provide textile treating compositions, methods and treated textiles which are free of chlorine-retention problems.

It is another object of this invention to provide textile treating compositions, methods and treated textiles where in crease-resistances are obtained which are substantially superior to crease-resistances obtained by most, if not all, prior textile treating compositions and methods.

A further object of this invention is the provision of novel textile treating compositions, methods and treated textiles wherein no narrowly critical controls in the ap plication of said compositions to textiles are necessary.

A still further object is the provision of textile treat ing compositions and treating methods for providing durable crease-resistance to textiles.

Further objects and advantages will be apparent from the following detailed description of several embodiments f this invention.

The novel textile creaseproofing compositions of this invention comprise a substantially non-aqueous solution of succinic anhydride or succinic acid or both and an acetate or carbonate salt including the acetate and car bonate salts of alkali metals, alkaline earth metals or organic tertiary amines or mixtures thereof. One highly advantageous aspect of this invention is the inclusion in the above-described composition of a suitable solvent in cluding acetic acid, acetic anhydride, pyridine, hydrocar hon-substituted pyridines or mixtures thereof. The novel textile treating method of this invention comprises the steps of heat-reacting succinic anhydride or succinic acid or mixtures thereof with a cellulosic textile in the presence of an acetate or carbonate salt including the acetate or carbonate salts of alkali metals, alkaline earth metals, or organic tertiary amines or mixtures of said acetate or p ice carbonate salts. More specifically, the novel textile treating methods of this invention include the application of the above-mentioned novel textile treating compositions to cellulosic textiles with the application of heat.

It has been found that the novel method can be carried out by application of the novel textile treating compositions to the cellulosic textile with the application of heat in substantially any mode. It is postulated that the crease-resistance obtained by the present invention is due to the reaction of succinic acid or anhydride with the cellulosic textile to provide cross-linkages, which reaction is carried out under such conditions, e.g., carbonate or acetate salt or solvent systems, wherein the amount of cross-linking appears to be regulated to prevent undue weakening, stiffening and/or dissolution of the textile while, at the same time, providing a superior degree of crease-resistance. Although the acetate or carbonate salts appear to be more than catalysts in the strictest sense of the Word and seem to have a regulatory eifect in addition to any catalytic efifect, such salts, nevertheless, will be referred to hereinafter as catalysts for simplicity. While we do not wish to be limited to any particular reaction mechanism or theory, the superior crease-resistance (Without accompanying weakening, stiffening, dissolution or other adverse effect on the textile being treated) is apparently due to the types of catalysts employed in the novel treating compositions and methods. Furthermore, particular solvent systems which can be employed under the invention apparently additionally affect the cross-linking mechanism to provide additional advantages. Best results obtained by the treating compositions and methods of this invention in relation to the mode of treatment, as will hereinafter be more fully described, appear to be due to the classes of catalysts and solvents employed.

In reacting succinic acid or anhydride with the cellulosic textile, it has been found that the presence of an acetate or carbonate salt of an alkali metal, an alkaline earth metal or an organic tertiary amine provides a superior crease-resistance without the undesirable effects of weakening, stiffening or dissolution of the treated textiles. The above-mentioned catalysts include sodium acetate, potassium acetate, potassium carbonate, lithium acetate, barium acetate, pyridine acetate and the like.

The catalysts and succinic acid or anhydride can be applied to the cellulosic textile in substantially any desired manner. For example, they may be dissolved in a suitable solvent and the cellulosic textile refluxed in the resulting solution for a sutlicient period to provide the desired crease-resistance. The time of refluxing is not narrowly critical and, for example, can range from 15 minutes or less to 2 /2 hours or more. Alternatively, the cellulosic textile can be padded with the above-mentioned solution to a suitable wet pickup, for example, 60 to weight percent, as best suits the particular equipment and production schedules selected, and the thus impregnated textile heated while preventing the escape of vapors, e.g., by wrapping the impregnated textile in aluminum foil or other impervious wrapper, for a length of time and at a temperature which would provide the desired superior crease-resistance but not so great that the textile would be heat-decomposed or heatweakened.

Still alternatively, the catalyst is dissolved in a suitable solvent for it, e.g., water, pyridine, acetic acid, methanol, acetic anhydride and the like, and the resulting solution applied to the cellulosic textile to impregnate same therewith. When the solvent for the catalyst employed is other than acetic acid, acetic anhydride, pyridine, hydrocarbon-substituted pyridine or mixtures thereof, the impregnated textile is dried to remove the solvent, but when the listed solvents are employed, drying is not necessary. The textile thus impregnated with the catalyst and dried or not dried, as the case may be, is then impregnated with succinic acid or anhydride which can be carried out by contacting the catalyst-impregnated textile with succinic acid or anhydride vapors in a nitrogen atmosphere at a temperature and for a time sulficient to provide the desired crease-resistance but not of such a degree to heat-weaken or heat-decompose the textile. In another alternative, the catalyst-impregnated textile can be dipped into a heated solution of succinic acid or anhydride (wherein, for example, the solvent is acetic acid, acetic anhydride, pyridine, hydrocarbonsubstituted pyridine or mixtures thereof) and held in such solution for a period of time sufficient to provide the desired crease-resistance. When the succinic acid or anhydride in this alternative is dissolved in acetic acid or anhydride or pyridine or a hydrocarbon-substituted pyridine, the time of dipping of the catalystimpregnated textile is not narrowly critical, whereas if other solvents are employed, it is preferred to minimize the time of dipping to provide the superior crease-resistance Without adverse effect on the textile. As a still further alternative, the catalyst-impregnated textile can be dipped directly into molten succinic acid or anhydride; in which case, the time of dipping is narrowly critical to avoid weakening or dissolution of the textile because of the extremely high concentration of succinic acid or anhydride in contact with the catalyst-impregnated textile.

Further advantageous results in providing superior crease-resistance without adversely affecting the physical characteristics of the cellulosic textile being treated are obtained by employing acetic acid or anhydride, pyridine, hydrocarbon-substituted pyridine or mixtures thereof as solvents for the succinic acid or anhydride and/or for the catalysts. Thus, the process reaction conditions, although not narrowly critical, are made still less critical and certain drying steps, necessary when other solvents are used, are avoided. For example, when Water or methanol, etc., is used as a solvent for the catalyst to provide a solution which is then applied to the textile prior to contact with succinic acid or anhydride, the water or methanol, etc., is preferably removed after impregnation and before contact with the succinic acid or anhydride. On the other hand, when acetic acid or anhydride, pyridine or hydrocarbon-substituted pyridine is employed as solvent, no subsequent drying or solvent removal step is necessary.

The amount of succinic acid or anhydride employed in relation to the quantity of cellulosic textile lies between that amount necessary to give the desired creaseresistance and that amount which adversely affects the physical properties of the textile to an objectionable degree; for example, dissolution, objectionable degree of weakening, objectionable degree of stiffening or the like. In general, a preferred range of succinic acid or anhydride to cellulosic textile ratio is from 3 weight percent to 30 weight percent of the succinic acid or anhydride based on the Weight of cellulosic textile.

The catalyst employed can be of any desired amount to provide a desired crease-resistance. In this regard, the amount of catalyst is not narrowly critical and can range as high as 400 weight percent or higher based on the Weight of succinic acid or anhydride and can range as low as 2 weight percent or lower on the same basis. When av solvent is employed, the solubility of the succinic acid or anhydride and a convenient percent of wet pickup on the textile being treated would be factors in determining the type and amount of solvents. When acetic acid or anhydride, pyridine, hydrocarbon-substituted pyridine or mixtures thereof are employed as solvents, the upper limit of solubility of both the succinic acid and/or anhydride and catalyst determines the maximum amount of these materials in the solvent. In general, it is preferred that: (1) the amount of solvent be in the range of 79.5 to 95 weight percent, (2) the range of succinic acid and/or anhydride be in the range of 0.5 to 5 Weight percent and (3) the range of catalysts be from 0.01 to 20 weight percent, all based on the total weight of the solution. These ranges, however, are not narrowly critical and are balanced with other desired process characteristics such as time and temperature of reaction, degree of wet pickup, the particular equipment employed and/or the particular produtcion schedules to be followed.

The following examples are presented. All percentages and parts set forth in the examples, unless otherwise indicated, are based on weight. Crease-resistance evaluations were made on a Monsanto Wrinkle Recovery Tester, and results obtained as the sum of the crease angles measured in the warp and filling directions.

EXAMPLE I A solution of 1000 parts acetic acid, 50 parts of succinic anhydride and 50 parts of sodium acetate was prepared. Cotton cloth weighing about 25 parts was immersed in the solution and heat was applied to bring the solution to reflux temperature. Refluxing under existing atmospheric pressure was continued for a period of about 2 /2 hours. After this time, the cotton cloth was removed, washed and dried. The cotton cloth thus treated had a dry crease-resistance of 260 and a wet crease-resistance of 218.

EXAMPLE II A solution of 1000 parts of pyridine, 50 parts of succinic anhydride and 25 parts of acetic anhydride was prepared. Cotton cloth weighing about 25 parts was immersed in the solution and heat applied to bring the solution to reflux temperature. Refluxing under existing atmospheric pressure was continued for a period of about 2 hours. After this time, the cotton cloth was removed, washed and dried. The cotton cloth thus treated had a dry crease-resistance of 274 and a wet crease-resistance of 207.

EXAMPLE III A solution of 1000 parts of acetic anhydride, 50 parts of succinic anhydride and 50 parts of sodium acetate was prepared. Cotton cloth weighing about 25 parts was immersed in the solution and heat was applied to bring the solution to reflux temperature. Refluxing under existing atmospheric pressure was continued for a period of about 2 /2 hours. After this time, the cotton cloth was removed, Washed and dried. The cotton cloth thus treated had a dry crease-resistance of 245 and a wet crease-resistance of 213.

EXAMPLE IV A solution of 500 parts of acetic anhydride, 500 parts of acetic acid, 50 parts of succinic anhydride and 25 parts of sodium acetate was prepared. Cotton cloth weighing about 25 parts was immersed in the solution and heat was applied to bring the solution to reflux temperature. Refluxing under existing atmospheric pressure was continued for a period of about 2%. hours. After this time, the cotton cloth was removed, washed and dried. The cotton cloth thus treated had a dry crease-resistance of 286 and a wet crease-resistance of 192.

EXAMPLE V The procedure of Example IV was followed with the exception that 50 parts of sodium acetate were employed instead of 25 parts. The cotton cloth thus treated had a dry crease-resistance of 301 and a wet crease-resistance of 191.

EXAMPLE VI The procedure of Example IV was followed with the exception that 25 parts of potassium acetate were employed in place of 25 parts of sodium acetate. The cotton cloth thus treated had a dry crease-resistance of 269 and a wet crease-resistance of 242.

8 EXAMPLE VII A solution of 500 parts of acetic acid, 500 parts of acetic anhydride, 100 parts of monoethyl ether of ethylene glycol, 50 parts of succinic anhydride and 50 parts of sodium acetate was prepared. Cotton cloth weighing about 25 parts was immersed in the solution and heat was applied to bring the solution to reflux temperature. Refluxing under existing atmospheric pressure was continued for a period of about 2 /2 hours. After this time, the cotton cloth was removed, washed and dried. The cotton cloth thus treated had a dry crease-resistance of 280 and a wet crease-resistance of 211.

EXAMPLE VIII A solution of 500 parts of acetic acid, 500 parts of acetic anhydride, 50 parts of succinic anhydride and 50 parts of potassium carbonate was prepared. Cotton cloth weighing 25 parts was immersed in the solution and heat was applied to bring the solution to reflux temperature. Refluxing under existing atmospheric pressure was continued for a period of about 2 /2 hours. After this time, the cotton cloth was removed, washed and dried. The cotton cloth was thus treated had a dry crease-resistance of 303 and a wet crease-resistance of 238.

EXAMPLE D( A solution of 50 parts of acetic anhydride, 50 parts of acetic acid, 5 parts of succinic anhydride and 5 parts of potassium acetate was prepared. Five samples of cotton cloth, each weighing about 25 parts, were immersed in the solution to a Wet pickup of about 85 weight percent. Each sample of impregnated cloth was then removed from the solution, wrapped in aluminum foil and placed in an oven operating at the temperature indicated in Table 1 below. Each sample of cloth was permitted to remain in the oven for the time indicated in Table 1 and after removal, washing and drying, had th wet and dry crease-resistances set forth in Table 1.

EXAMPLE X A solution of 500 parts acetic anhydride, 500 parts acetic acid, 50 parts succinic anhydride and 100 parts sodium acetate was prepared. Two samples of cotton cloth, each weighing about 25 parts, were immersed in the solution and heat was applied to bring the solution to reflux temperature. Refluxing under existing atmospheric pressure was continued for a period of about 2 /2 hours. After this time, the samples of cotton cloth were removed, washed and dried. Each sample thus treated had a dry crease-resistance of 244.

One sample was subjected to five washes in a Bendix automatic washer under normal home conditions (at a Wash temperature of about 140 F. and using All detergent manufactured by Monsanto Chemical Company). The first four washes involved the cycle of washing, spinning, rinsing, and spinning followed by tumble-drying. The fifth wash was the same except that the sample was press-dried instead of being tumbledried. At this point the sample showed a dry creaseresistance of 257. The sample was then subjected to five more Bendix washes and dryings as described above, after which it was found to have a dry crease-resistance of 260. The sample was then subjected to ten more Bendix washes and dryings as above, after which it was found to have a dry crease-resistance of 245.

The second treated sample was subjected to one commerical wash (similar to ASTM Test D416-54T, Test No. 3) and was found to have a dry crease-resistance of 257. The sample was subjected to four more commercial washes, after which it was found to have a dry creaseresistance of 237.

EXAMPLE XI The procedure of Example IV was followed with the exception that 20 parts of succinic anhydride instead of 50 parts thereof were used and 20 parts of lithium acetate were used in place of 25 parts of sodium acetate. The cotton cloth thus treated had a dry crease resistance of 227 and a wet crease resistance of 233.

All of the cloth treated as described in all of the foregoing examples possessed a satisfactory hand, was free of any chlorine retention difliculties or drawbacks and was not objectionably weakened by the respective treatments.

The alkyl-substituted pyridines, e.g., lutidines, picolines, collidines and the like provide similar results when substituted for pyridine in the above examples which employ pyridine.

What is claimed is:

1. A method for improving the crease resistance of cellulosic textiles which comprises contacting the cellulosic textiles with a succinic compound selected from the class consisting of succinic acid, succinic anhydride and mixtures thereof, and a substance selected from the class consisting of alkali metal and alkaline earth metal carbonate and acetate salts and carbonate and acetate salts of organic tertiary amines and mixtures thereof in the presence of an acetic acid-acetic anhydride solvent at the reflux temperature of said solvent.

2. The method as claimed in claim 1 wherein said substance is sodium acetate.

3. The method as claimed in claim 1 wherein said substance is potassium carbonate.

4. A textile creaseproofing composition for cellulosic textiles comprising a non-aqueous acetic acid-acetic anhydride solution of a succinic compound selected from the class consisting of succinic acid, succinic anhydride and mixtures thereof, and a substance selected from the class consisting of alkali metal and alkaline earth metal carbonate and acetate salts and acetate and carbonate salts of tertiary organic amines and mixtures thereof.

5. A textile creaseproofing composition as claimed in claim 4 wherein said substance is sodium acetate.

6. A textile creaseproofing composition as claimed in claim 5 wherein said substance is potassium acetate.

7. A cellulosic textile treated by the method claimed in claim 1.

References Cited in the file of this patent UNITED STATES PATENTS 1,878,783 Landolt Sept. 20, 1932 1,930,985 Haller et al. Oct. 17, 1933 2,170,024 Heckert Aug. 22, 1939 Touey .--:'?:-,-1-r.-7-.-

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No 3 l l8 O2l September 8 1964 Thomas Allen et all,

It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as c orrec ted below Column 6 line 5'? for the claim reference numeral "'5" read l "u Signed and sealed this 4th day 0f May 1965,

(SEAL) Anest:

ERNEST W. SWIDER EDWARD J. BRENNER Attesting Officer Commissioner of Patents 

1. A METHOD FOR IMPROVING THE CREASE RESISTANCE OF CELLULOSIC TEXTILE WHICH COMPRISES CONTACTING THE CELLULOSIC TEXTILES WITH A SUCCINIC COMPOUND SELECTED FROM THE CLASS CONSISTING OF SUCCINIC ACID, SUCCINIC ANHYDRIDE AND MIXTURES THEREOF, AND A SUBSTANCE SELECTED FROM THE CLASS CONSISTING OF ALKALI METAL AND ALKALINE EARTH METAL CARBONATE AND ACETATE SALTS AND CARBONATE AND ACETATE SALTS OF ORGANIC TERTIARY AMINES AND MIXTURES THEREOF IN THE PRESENCE OF AN ACETIC ACID-ACETIC ANHYDRIDE SOLVENT AT THE REFLUX TEMPERATURE OF SAID SOLVENT. 